Gravitational Wave Measurements

Home , GW170608, GW170817

Reed Essick IPA Oct 9, 2018 Our detectors

LHO Virgo Hanford, WA Pisa, Italy LLO KAGRA Livingston, LA Kamioka Mine, Japan

2 Our detectors

← GW150914 ← LVT151012 ← GW151226 ← GW170104 ← GW170608 ← GW170814 ← GW170817

3 Abbott+(2018) Our detectors

4 Abbott+(2018) Our detectors

circa GW170817

5 Abbott+(2018) Our detectors

6 Abbott+(2018) Types of signals that have been observed

7 LIGO-Virgo (Frank Elavsky, Northwestern) Types of signals that have been observed

pair-instability SN

8 arXiv:1709.08584 Types of signals that have been observed

2 ~ad hoc models, both are consistent with a constant merger rate as a function of redshift. 9 arXiv:1805.10270 Science enabled by observed signals

Tests of General Relativity speed of gravity/mass of graviton: ApJL 848, 2 (2017) implications for early-universe cosmology: PRD 97, 084005 (2018) deviations from post-newtonian waveform: PRL 116, 221101 (2016) scalar, vector vs. tensor polarizations: PRL 119, 141104 (2017) limits on the number of spacetime dimensions from GW170817: arXiv:1801.08160 (2018) and many more!

PRL 116, 221101 (2016)

10 Science enabled by observed signals

GW150914 (see ApJL 818, 2 (2016)) Big black holes exist and merge! stellar and galactic physics → Relatively weak stellar winds (at low metallicities) → SN kicks must be relatively small to keep system bound Possible formation channels → isolated evolution → dynamical interactions within Globular Clusters These could be distinguished by the component spins and their alignment with the orbital angular momentum or by the precise merger rate as a function of redshift.

GW170817 (see ApJL 850, 2 (2017)) As long as merger delay times are ≳ 1 Gyr, constraints do not strongly depend on Galaxy profile, Star Formation Rate, etc → at a projected distance of ~ 2kpc, dynamical timescales within the galaxy are ~20 Myr → SN kicks must be relatively small to keep system bound

“An increased source sample resulting from future GW data will of course better constrain the merger rates, but will also allow us to probe the mass distributions and any dependence on redshift. To go beyond the current, mostly qualitative discussion, and move toward comprehensive model constraints, it will be important to develop frameworks that account for observational biases and for appropriate sampling of the model parameter space including relevant parameter degeneracies.”

11 Science enabled by observed signals

Neutron Star Equation of State measurements Tides!: arXiv:1805.11579 (2018) Equation of State inference: arXiv:1805.11581 (2018)

R(m, stiff) Λ(m, stiff) R(m, soft) Λ(m, soft)

stiff → large radii soft → small radii

For the same mass, soft EOS “collapse more” under their own weight.

12 Science enabled by observed signals

Neutron Star Equation of State measurements Tides!: arXiv:1805.11579 (2018) Equation of State inference: arXiv:1805.11581 (2018)

R(m, stiff) Λ(m, stiff)

Tidal factor: ε ~ R/a

R(m, soft) Λ(m, soft) a

13 Science enabled by observed signals

Less Compact Neutron Star Equation of State measurements Tides!: arXiv:1805.11579 (2018) Equation of State inference: arXiv:1805.11581 (2018)

More Compact

14 Science enabled by observed signals

Neutron Star Equation of State measurements Tides!: arXiv:1805.11579 (2018) Equation of State inference: arXiv:1805.11581 (2018)

favor softer EOS

Abbott+ (2018)

15 Science enabled by observed signals

Neutron Star Equation of State measurements Tides!: arXiv:1805.11579 (2018) Equation of State inference: arXiv:1805.11581 (2018)

16 Abbott+ (2018) Science enabled by observed signals Nonlinear Tidal instabilities modes’ dynamics described in a spherical harmonic Galerkin decomposition

Tides excite stellar normal modes, which evolve independently in l=1 l=2 l=3 l=4 l=5 linear theory.

Nonlinear interactions couple (many) different modes together with associated coupling nonlinear coefficients and instability coupling thresholds. linear tide daughter modes The p-g instability couples the linear tidal bulge to a high-frequency p-mode and a low-frequency g-mode. This instability grows secularly throughout the orbit once tripped. 17 Science enabled by observed signals

24 km 4.1 km

247 km

Nonlinear Tidal instabilities p-g secular tidal instability could introduce phase shifts into the observed waveform by providing an additional energy loss mechanism.

“past-aligned” waveform

Essick+ (2016)

p-g instability turns on at 18 fGW ~ 50 Hz Science enabled by observed signals ≲1% of energy radiated as GWs

Nonlinear Tidal instabilities p-g secular tidal instability could introduce phase shifts into the observed waveform by providing an additional energy loss mechanism.

Abbott+ (2018) 19 What I’m personally excited about for O3

new signals and more signals

Abbott+(2018)

20 What I’m personally excited about for O3 data quality automation

GW170817

Abbott+ (2017)

automatically available within 9 sec References

GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral. PRL 119, 161101 (2017). Prospects for observing and localizing gravitational-wave transients with Advanced LIGO, Advanced Virgo and KAGRA. Living Reviews in Relativity (2018) Limits on the number of spacetime dimensions from GW170817. arXiv:1801.08160 Astrophysical Implications of the binary black hole merger GW150914. ApJL 818, 2 (2016). Speed of gravitational waves and black hole hair. PRD 97, 084005 (2018). GW170817: Measurements of neutron star radii and equation of state. arXiv:1805.11581 (2018). Properties of the binary neutron star merger GW170817. arXiv:1805.11579 (2018). GW170814: A three-detector observation of gravitational waves from a binary black hole coalescence. PRL 119, 141101 (2017). Tests of General Relativity with GW150914. PRL 116, 221101 (2016). Gravitational waves and gamma-rays from a binary neutron star merger: GW170817 and GRB170817A. ApJL 848, 2 (2017). Estimating the contribution of dynamical ejecta in the kilonova associated with GW170817. ApJL 850, 2 (2017). On the progenitor of binary neutron star merger GW170817. ApJL 850, 2 (2017). How many kilonovae can be found in past, present, and future survey data sets? ApJL 852, 1 (2017). A gravitational-wave standard siren measurement of the Hubble constant. Nature 551, 85-88 (2017). Precision standard siren cosmology. arXiv:1712.06531 (2017). Where are LIGO's big black holes? ApJL 851, 2 (2017). Does the black hole merger rate evolve with redshift? arXiv:1805.10270 (2018). Observational selection effects with ground-based gravitational wave detectors. ApJ 835, 1 (2017). Impact of the tidal p − g instability on the gravitational wave signal from coalescing binary neutron stars. PRD 94, 103012 (2016). Constraining the p-mode -- g-mode tidal instability with GW170817. arXiv:1808.08676.

Detection Methods

unmodeled searches

24 Detection Methods

matched filter

25 Science enabled by observed signals Nonlinear Tidal instabilities

Hpg is consistent with H!pg for shared parameters.

Hpg shows consistent behavior with single-IFO and HLV data.

-7 Bounds: A0 ≤ 3.3x10 f0 ~ 70 Hz rule out only the most extreme -6 theoretical predictions (A0~10 )

Fig. 2 26 Challenges

● ~200,000 channels per site ○ ~6,000 “fast” channels ESD Saturation ● Glitch rates ~1/100 sec ○ Non-stationary!

● post facto ○ latency < 60 sec ● pre-filtering ○ latency < 1 sec GW170817 Challenges

GW170817

automatically available within 9 sec Challenges

AUX Challenges

AUX Challenges GW

AUX